Inappropriate placement of urinary catheters into the ureter: A case report and literature review

Objective: To emphasize preventive measures and outline management strategies for inadvertent ureteral cannulation. Methods: We present a case report and conduct a literature review of 39 case reports on ureteral cannulation, examining a total of 48 patients. Results: About 67% of the cases were female, and long-term catheterization was observed in 67% of the cases. Neurological conditions such as spinal cord injury (SCI), stroke, dementia, multiple sclerosis, and myasthenia gravis were the primary factors (48%) in ureteral cannulation. Symptoms included flank pain (46%), fever (31%), oliguria (27%), non-deflatable balloon issues (25%), hematuria (21%), abdominal pain (17%), urine leak (12.5%), and nausea/vomiting (8%). Complications varied, including acute pyelonephritis (35%), acute kidney injury (27%), urosepsis (21%), and ureter rupture (17%). Despite inadvertent catheter placement, 25% of patients had no complications. More than half of the patients (58%) were managed through catheter change, while 27% underwent cysto-ureteroscopy with or without balloon puncture or ureteral stenting. Additionally, 10% received interventional radiology procedures, 6.25% underwent surgical repair, and 4% underwent ultrasound-guided balloon puncture. Conclusions: Female gender, neurologic conditions, and long-term catheterization were identified as predominant risk factors. Early detection of ureteral cannulation can prevent severe complications, particularly in certain special populations such as patients with neurogenic bladder or SCI, who may have reduced sensation and expression capabilities.


Introduction
Urinary catheterization is clinically widely performed and is considered a comparatively safe procedure.However, the misplacement of a catheter into the ureter, which leads to serious complications, is considered troublesome.Herein, we present a case report and conduct a literature review of 39 case reports on ureteral cannulation, examining a total of 48 patients.

Patient Information
A 82-year-old man with a history of prostate cancer and stroke, who is completely dependent on activities of daily living (ADLs), visited our emergency department due to shortness of breath and a spiking fever for the past 2 days.He had a suprapubic catheter (SPC) created 8 years ago for the neurogenic bladder.A routine SPC change (16 Fr.Foley Catheter) by a urologist 1 week before he visits the emergency department.Upon arrival, his vital signs were as follows: body temperature of 39.1°C, heart rate of 132/min, blood pressure of 82/52 mm Hg, respiratory rate of 26/min, with oxygen saturation of 97% on a 6 L/min O 2 mask.A preliminary diagnosis of septic shock was made.His physical examination findings were unremarkable, and he was unable to express himself well due to history of stroke and current bedridden status.Low urine output was discovered by his family after the SPC was changed.
The authors have no funding and conflicts of interest to disclose.

All data generated or analyzed during this study are included in this published article [and its supplementary information files].
We confirm that all ethical guidelines and regulations were strictly followed throughout the preparation of this case report.Written informed consent was obtained from the next of kin of the patient.This manuscript has not been published or presented elsewhere in part or in entirety and is not under consideration by another journal.

Management
The SPC was deflated and replaced with another 16 Fr.catheter, immediate ultrasound was conducted to confirm the balloon position.The patient required inotropic support for an additional 36 hours, and an empirical antibiotic (piperacillintazobactam) was administered for pneumonia and pyelonephritis.His urine culture revealed Enterococcus faecalis and Acinetobacter baumannii complex (XDRAB).Piperacillintazobactam was replaced by colistin on day 10.He was discharged after a 25-day hospital course.

Literature Review
Urinary catheterization is clinically widely performed and is considered a comparatively safe procedure, particularly among patients with neurogenic bladder.Catheter-related minor complications, such as urinary tract infections (UTIs), bleeding, urethral injury, catheter malfunction, entry into a false route, and retention of the catheter balloon in the urethra, are reported. [1,2]erious complications rarely occur, and the misplacement of a urinary catheter into the ureter, leading to ureter rupture is considered troublesome.Iatrogenic or externally induced trauma are the predominant causes of ureteral injuries, with the former arising from urologic procedures (42%), gynecologic interventions (34%), and general surgical interventions (24%). [3,4]nflation of a misplaced catheter balloon within the ureter could cause ureter rupture, which can lead to numerous complications, including abscess formation, urinomas, and urosepsis, requiring prompt evaluation and intervention. [5]his was the only case of a SPC misplaced into the ureter from our hospital, impelling us to review the literature for similar cases.We searched the published case reports and literature reviews, encompassing 39 case reports on ureteral cannulation.A total of 48 patients were examined, and our reviews are the most integrated to date.The details of these cases are listed in Table 1.  Patie demographics and clinical characteristics are summarized in Tables 2 and 3.

Results
The median age was 64 years (range, 7-86 years).About 67% of the cases were female, and it is noteworthy that there were 3 pediatric cases.Regarding the side of cannulation, 40% were on the left side, and 60% on the right.Long-term catheterization was observed in 67% of the cases, with 29% not requiring a longterm catheter.The catheter sizes, with the majority (48%), are not specified (N/A).Among specified sizes, 16 Fr.catheters were most common (25%), followed by 14 Fr.(10%) and 12 Fr.(6%).
Neurologic conditions (spinal cord injury [SCI], stroke, dementia, multiple sclerosis, myasthenia gravis) played a predominant role (48%) in ureteral cannulation, emerging as the most significant factor among the underlying conditions examined.They contributed nearly half (23/48) of the cases, followed by pregnancy (10%).Other risk factors are detailed in Table 2. Additionally, 63% of patients had neurogenic or contracted bladders, while 33% did not.In terms of the patients' ADLs, 38% were dependent, and 56% were independent.It's important to note that ADLs may not directly correlate with ureteral cannulation.
Consequences of ureteral cannulation were diverse, with acute pyelonephritis affecting 1-third of patients (35%), acute kidney injury (AKI) in 27%, urosepsis in 21%, ureter rupture in 17%, and no related mortality.The only 2 mortalities were due to unrelated sepsis (lung cancer progression and osteomyelitis).Despite the inadvertent placement of urinary catheters, 1-quarter of patients (25%) underwent the procedure without any complications or adverse events.
More than half of the patients (58%) were managed through catheter change, while 27% underwent cysto-ureteroscopy with or without balloon puncture or ureteral stenting.Additionally, 10% received interventional radiology procedures (antegrade double-J stent placement or nephrostomy), 6.25% underwent surgical repair, and 4% underwent ultrasound-guided balloon puncture.Two out of 3 cases with ruptured ureters, discovered incidentally during the operation, underwent surgical repair.One case received debulking surgery, while the other underwent ileal conduit surgery.

Discussion
Risk factors for unintended ureteral cannulation have been delineated in the literature [27,31] : 1. Female anatomy.The female urethra, being shorter than the male urethra, may be susceptible to misdirection during catheter insertion due to the angle at which the catheter enters the bladder.A similar theory applies to SPC. 2. Pregnancy-related changes.Physiological alterations during pregnancy, attributed to elevated progesterone levels, are recognized for inducing the dilatation of the ureter. [45]. Neurological disorder (SCI, stroke, dementia, multiple sclerosis): SCI can result in an upper motor neuron syndrome, leading to bladder hyperactivity characterized by spasms, urgency, and incontinence.Over time, this can lead to reduced bladder capacity and heightened bladder pressures, contributing to increased vesicoureteral reflux.The delayed presentation is attributed to the sensory dysfunction of the bladder, [46,47] patients' inability to feel pain or communicate, resulting in acute pyelonephritis (30%) and AKI (28%).4. Long-term catheter: The bladder tends to contract and decrease its capacity, and frequent catheter changes, as a Li and Au • Medicine (2024) 103:15 Medicine result, they have more opportunities for the catheter to be misplaced into the [27] 5. Neurogenic/contracted bladder: Vesicoureteral reflux with patulous ureteral orifices may facilitate catheter entry into the ureter.6. Catheter size: Does not appear to be a predisposing risk factor, as misplacement reported with the smallest size of 12 Fr.and the largest size of 30 Fr.However, it's important to note that this observation requires further clarification, as a significant portion of the data was missing.7. Age, laterality, ADLs: Not relevant (further clarification is needed).

Key takeaway
What can be done if the balloon in the ureter is non-deflatable? [48]Deflate the balloon using conventional manual syringe aspiration. If these methods prove unsuccessful, alternatives such as cutting off the inflation channel, or bursting the balloon with a guidewire applied through the inflation channel. Seeking specialized medical assistance, consulting with an interventional radiologist or urologist may be necessary for ultrasound-guided/cysto-ureteroscopy balloon puncture.
How to misplacement of a urinary catheter into the ureter? It is essential to be mindful of certain factors that increase the risk of misplacement, particularly in female patients, those with neurological disorders, neurogenic or contracted bladders, and individuals with long-term indwelling catheters. To confirm proper urinary catheter placement, it is advisable to ensure urine flow before inflating the balloon.Subjective resistance during inflation may indicate an inappropriate position. If the catheter is inserted without urine output, a saline flush is recommended to ensure the catheter is unobstructed. [49] For urethral catheters, verifying the appropriate length outside the urethra is crucial. Similarly, for suprapubic catheters, measuring the length of the initial catheter and marking the corresponding length on the replacement catheter helps ensure correct placement at the proper depth. [50] During balloon inflation, careful observation for any accompanying pain is necessary, although this may not be apparent in patients with sensory disorders. Consider using short-tip [27,31] or blunt-tip urinary catheters, such as silicone nephrostomy catheters with an openend, blunt-tip, and a smaller size balloon, as replacements for urethral catheters. At the conclusion of the procedure, gently withdrawing the catheter to the bladder neck is recommended for a safe process. [21]at if inadvertent ureteral cannulation occurs?
1.If there is suspicion of catheter misplacement into the ureter, conducting an ultrasound examination as the initial diagnostic choice to determine its location and the presence of hydronephrosis.A contrast-enhanced CT scan, a noninvasive study, serves as a definitive tool to assess complications, particularly ureteral rupture.Exercise caution in cases involving patients with AKI. 2. Patients without ureteric injury may undergo conservative management, involving catheter change or removal, along with antibiotic treatment for UTIs.3. In instances of ureteric rupture, urinary diversion becomes imperative, achieved through either the insertion of a ureteric stent or percutaneous nephrostomy.Surgical repair is warranted for severe ureteric injury.

Limitations
The limitation of this article is the small number of cases, with each article only able to present as a case report or case series.However, our review is the most comprehensive literature review to date.

Conclusion
This article presents a noteworthy case, coupled with an extensive literature review, shedding light on the complexities of ureteral misplacement.Early detection, intervention, and a multidisciplinary approach are crucial in cases of ureteral misplacement.It emphasizes the importance of considering patient risk factors, diagnostic approaches and employing appropriate techniques during catheterization procedures.

Figure 1 .
Figure 1.The patient's serum creatinine levels over time.

Figure 2 .
Figure 2. Abdomen and pelvic CT revealed (A-C) misplacement of the SPC tip (arrow) into the right ureter (D) right hydronephrosis (arrow) with perinephric fat stranding.

Table 1
Detailed information of the cases included in the literature review.

Table 2
Patient demographics of ureteral cannulation in the literature review (39 case reports).